A certain fluorine-containing polymer is known to be able to provide excellent water-repellency, oil-repellency, antifouling property, surface slip property, or the like when it is used on a surface treatment of a base material. A layer (hereinafter, referred to as a “surface-treating layer”) formed from the surface-treating composition comprising a fluorine-containing polymer is applied to various base materials such as a glass, a plastic, a fiber and a building material as a so-called a functional thin film.
As such fluorine-containing polymer, a fluorine-containing polymer (hereinafter, referred to as a “fluorine-containing silane polymer) which has a hydrolyzable group bonding to a Si atom in its molecular terminal is known (see Patent Literatures 1 and 2). This fluorine-containing silane polymer is a reactive fluorine-containing polymer wherein the hydrolyzable group bonding to a Si atom reacts and bonds in between the base material and the polymers.